Strap joint and method of using same



Sept. 10, 1940. J. E, OTT

STRAP JOINT AND METHOD oF Usme SAME Filed uarn 1, 1957 Patented Sept. 10, 1940 UNITED STATES PATENT OFFICE J ohn Ekern Ott, Lisle Township, Du Page County, Ill., assigner to Acme Steel Company, Chicago, Ill., a corporation of Illinois Application Marchi, 1937, serial N0. 128,450

6 Claims.

This invention relates to improvements instrap joints and methods of using the same and its purpose is to provide an improved joint adapted primarily for temporarily holding the ends of a flexible binder in overlapping relation preliminary to the formation of a permanent joint, which is preferably formed by utilizing certain parts which constitute the temporary joint. The principal object of the invention is to provide an improved joint by which the overlapping ends of a fiexible binder may be frictionally heldin overlapping relation. A further object of the invention is to provide a strap joint comprising a sleeve adapted to receive the overlapping ends of a metal strap having parts by which these ends are wedged into frictional engagement with each other and with the surrounding sleeve. Another object of the invention is to provide an improved joint which may be utilized, for example, in the formation of a bale by an improved method according to which the joint is utilized for holding in overlapping relation the ends of each of a plurality of flexible binders which extend around the bale, whereby all of the binders are put in position and drawn substantially taut with their ends secured in overlapping relation by the improved joint, prior to bringing into operation a sealing tool by which a permanent interlocking joint is formed between each pair of overlapping strap ends. This improved method is described and claimed in my copending divisional application Serial No. 225,678, led August 19, 1938. Other objects relate to various features of construction of the improved joint which will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawing in which one form of the improved joint and one example of the method of utilizing it are illustrated.

In the drawing- Fig. 1 shows an end elevation of a bale press and bale, disclosing the method of applying the bale binding straps thereto and the connection of the ends thereof by means of the improved joint of the present invention;

Fig. 2 is a perspective view of the seal which encloses the overlapping strap ends in forming the improved joint of the present invention;

Fig. 3 is a perspective view of the end portions of a strap which has one end deformed to cooperate with the seal illustrated in Fig. 2; Fig.` 4 is a perspective view of one end of the strap shown in Fig. 3 having applied thereto the (Cl. .Z4-23) seal illustrated in Fig. 2, in readiness: to receive within the seal the other end of the strap;

Fig. 5 is a perspective View showing the overlapping ends of the strap embraced by the tubular seal, after the free end of the strap has been `5 threaded through the seal beneath that end of the strap which is deformed and preliminary to forcing the surrounding seal to its final position;

Fig. 6 is a perspective view similar to that of Fig. 5 showing the overlapping strap ends and the surrounding seal after the seal has been forced downwardly to bring about a wedging engagement with the deformed end of the strap;

` Fig. 7 is a perspective view similar to that of Fig. 6 showing the completed interlocking joint which is formed by shearing the lateral edges of the strap and seal shown in Fig. 6 and effecting a lateral deiiection of the metal between the points where the shearing cuts are made;

Fig. 8 is a transverse sectional View taken on the line 3 9 of Fig. 6;

Fig. 9 is a longitudinal sectional view taken on the line 9 9 of Fig. 6.

The improved joint of the present invention is capable of being used with particular advantage in practicing an improved method of forming a bale, such as a bale of cotton or other com-- pressible material, which is ordinarily provided with a protective covering preliminary to being bound together and reenforced by flexible binders, such as surrounding steel straps or the like. In the formation of such bales according to methods heretofore practiced, there has been great diculty and inconvenience encountered by reason of the fact that the overlapping strap ends could not be maintained in assembled relationship to an enclosing seal, with the strap in taut condition, during the operation of a sealing tool for deforming the seal and overlapping strap ends to provide an interlocking joint, and it has `been necessary, heretofore, to form a complete interlocking joint between the overlapping ends of each strap before drawing taut and forming similar joints between the overlapping ends of 45 other binders passed around the bale. The actuation of a sealing tool for forming an interlocking joint between overlapping strap ends ordinarily requires the use of both hands of the operator and it has therefore been diiiicult or 50 impossible for the operator, at the same time, to hold an enclosing seal in proper relationship to the overlapping strap ends between which the interlocking joint is to be formed by the deformation of the seal and strap. This difficulty is overi come in the present invention by the use of the improved seal which embraces the overlapping strap ends and holds them frictionally in proper relationship to each other until the complete interlocking joint is formed, thus making it unnecessary for the seal and strap ends to be held by the operator during the action of the tool and making it possible for all of the seals and their associated overlapping strap ends to be placed in proper relative positions to receive the sealing tool before actuating the sealing tool to form any of the interlocking joints.

In Fig. 1 of the accompanying drawing there is illustrated a portion of a bale press ificomprising a lower movable pressure platen i carried by a plunger it which is movable vertically within the upwardly projecting standardsi l carried by the base i8. An upper stationary pressure platen i9 is mounted on the upper ends of the standards il. The plunger it is adapted to be actuated by a suitable mechanism for forcing the platen l5 upwardly towards the pressure platen i9, thereby compressing the intervening bale 2i), which may be a bale of cotton or other compressible material. The bale it has a cover 20l of cloth, paper, or the like, the overlapping edges of which are secured together by stitches as shown at 26h. The component parts of the bale are secured in assembled relation with respect to each other by a number of surrounding flexible b-inders 2i which are illustrated as being in the form of iiat iiexible steel straps having their overlapping ends secured together by sealed joints employing seals 23. The lower pressure platen is provided in its upper face with a plurality of parallel grooves i5a, of rectangular cross section, to receive the straps 2i during the process of applying the straps to the bale, and, for the same purpose, the upper pressure platen l@ is provided in its lower face with a plurality of similar parallel grooves ige, each of which is adapted to register in a vertical plane with one of the grooves ESE.

The straps 2i which are used to bind the bale 20 are in the form of fiat iiexible steel straps having some degree of stiffness but having sutil-- cient ductility to permit them to be drawn into tight engagement with the surfaces of the bale when they are drawn taut. This strap is ordinarily supplied in the form of coils which may be located at the place where the bales are being bound and, as the strap is withdrawn from a coil, successive portions thereof are cut to the proper length for surrounding the bale, with the ends of each length overlapping after it has been drawn taut. One end of each length of strap is deformed by providing a longitudinal tapered rib 2th therein, and a corresponding tapered groove on the opposite side of the strap. The provision of this rib Rib provides an inclined wedging surface which diverges from the plane of the strap toward the extremity thereof, the end of the strap being preferably curved as shown at 2i?. Each length oi strapI may be cut from the source of supply, in the held o operation, by a suitable tool adapted to sever the strap and at the same time the rib on one of the cut ends, the other cut end remaining flat. Certain forms of tools adapted for this purpose are described and claimed in my copending application Serial No. 158,350, filed August 13, 1937.

lThe wedging surface provided by the rib 2th is adapted to cooperate with a surrounding tubular seal 23 which is threaded onto each strap 2l over the opposite :dat extremity 2id thereof. Each seal Z3 is in the form of a flat open tube having side flanges 23a which are reversely bent and which have their edges 23O spaced apart, as shown in Figs. 2 and 8, to leave a longitudinal slot between them. The opposite wall of each seal is provided with inwardly punched projections which may be in the form of a pair of circular debosses 2SC or in the form of lettering representing a trade-mark, or the like. These projections 23C are located at equal distances from the ends of the seal, so that it is immaterial which end of the seal rst engages the strap end when the seal is threaded onto a strap. The inwardly punched projections 23C areA adapted to cooperate with the inclined wedging surfaces on the strap ends, thereby forcing the overlapping strap ends against the opposite flanges 23a of the seals when the parts are assembled as shown in Fig. 9.

After the straps 2l of the required length have been cut from thesource of supply with the simultaneous formation of a rib 2lb on one end oi each strap, one of the seals 23 is threaded onto each strap, with the inwardly extending projections 23S on the side of the strap on which the rib 2lb is formed, until the seal occupies a position in proximity to that rib. In order to prevent the seals from being accidentally removed from the straps after being thus threaded therein, the straps may be bent transversely near the seals preliminary to the step of placing the straps around the bale which is t'o be bound. According to the preferred practice, the bale 2G, having the component parts of the cover 26a in position with respect thereto, is placed on the lower platen t5 of the press, shown in Fig. 1, and this lower platen is then moved upwardly by actuating the plunger it? until the bale has been compressed substantially between the upper and lower piatens. The series or straps on which the seals have previously been threaded are then put in place by threading one of the straps through each of the grooves i921 which are formed in the upper platen i9 until the end of each strap carrying the seal hangs down over the upper edge of the bale near the top thereof, as shown by dotted lines in Fig. 1. The upper ends or the straps and the seais carried thereby will then have the appearance shown in Fig. i and the opposite end portions of the strap will be hanging down at the other side oi the bale. The next step is to thread these dat ends 2 id of the straps through slots ia which are formed in the lower pressure platen i5, with one strap occupying eachY slot directly below the portion of the same strap which occupies a groove in the upper platen. All of the straps will then have the position shown by dotted lines in Fig. 'i and the next step is to thread the free end 2id of each strap through the seal 23 which is carried by the end 2 la of the same strap. This is done by elevating the seal slightly on the strap and inserting the end 2 ld through the seal on the side thereof adjacent the flanges 23a, as shown in Fig. 5. After inserting the end Id of each strap through the seal on the same strap, the strap is drawn as taut as possible by hand and, during this operation, the operator located adjacent the seals may have the assistance of another operator at the other side of the bale who will push inwardly the bowed portion 2 Ie of each strap, which is shown by dotted lines in Fig. l. After a strap has thus been drawn as taut as possible, the seal 23 thereon is forced downwardly from the position shown in Fig. 5 to the position shown in Fig. 6, thereby causing the lower projection 23C on the seal to ride outwardly on the wedging surface of the rib 2 Ib, thereby forcing the end 21a of the strap into quite frictional engagement with the end 2id of the strap which is at the same time for-ced int'o quite frictional engagement with the flanges 23a of the seal, as shown in Figs. 3 and Si. A frictional grip is thus established between the overlapping strap ends and the seal which maintains these parts in assembled relation until a permanent interlocking joint is formed. After a temporary joint has been formed, as shown in Fig. 6, a permanent joint is then made by deforming the seal 23 and the enclosed overlapping strap ends and this may be done by providing the form of interlocking joint disclosed in the United States patent of Ralph H. Norton No. 1,26G,16, dated March 19, 1918, or by providing any other suitable form of interlocking joint. The joint disclosed in said patent may be conveniently formed by the use of a suitable sealing tool of the form described and claimed in the United States patent ofChester M. Mac- Chesney and John Ekern Ott No. 1,730,669, dated October 8, 1929. In the operation of this sealing tool, which is shown at 25 in Fig. 1, the two handies thereof may be grasped by the hands of the operator and the jaws of the tool brought into engagement with opposite sides of each of the seals shown in Fig. 6, thereby forming a complete interlocking joint having the form illustrated in Fig. 'i where the lateral edges of the strap and seal are sheared along transverse lines 23d with the metal between the two cuts at each side of the seal deflected transversely to form angular lugs 23e, so that the abutting edges of the strap and seal prevent relative longitudinal movement of the overlapping strap ends. If desired, one operator may form these interocking joints with the use of the tool 25 following the `formation by another operator of the temporary joint shown in Fig. 6. Whatever procedure is followed, the formation of the temporary frictional joint shown in Fig. 6 holds the seals and the overlapping strap ends in proper assembled relationship so that an operator can quickly form interlocking joints at the overlapping ends of each strap. When all of the complete joints, having the form shown in Fig. '7, have been completed, or while they are being completed, the parts of the `cover 2l)2L are folded and sewed together and the lower pressure' platen I is then moved downwardly to release the pressure on the bale which then expands and causes all of the binding straps 2| to be drawn taut in close proximity to the surfaces of the bale. In order to secure the best results in the completed bale, the operator should draw all of the straps to substantially the same degree of tautness by hand while the bale is Icompressed and during the operation of forming the temporary joints shown in Fig. 6.

Although one form of the improved seal and one form of the improved sealed joint have been shown and described in connection with the disclosure of one method of forming a bale with the use of this seal and this joint, it will be understood that the seal and joint employed in the practice of that method may be modified n various ways without departing from the scope of the appended claims.

I claim:

1. A strap joint comprising overlapping strap ends, one of which has a part provided with a wedging surface, and a seal embracing said strap ends and having a part engaging said wedgingv surface 'to cause said seal and said strap ends to exert a frictional grip upon each other, the other strap end being straight and free to move with respect to said first named strap end except for frictional contact therewith and with said seal.

2. A strap joint comprising overlapping strap members and a seal member, said seal member embracing said strap members, one of said strap members being straight and being free to move within the said seal member except for frictional contact therewith and with the other strap member, one of said members having a part provided with a wedging surface adapted to engage another of said members to Cause said members to exert a frictional grip upon each other.

3. A strap Vjoint comprising flat overlapping strap members, and a tubular seal member embracing said overlapping strap members, one of said members having a part provided with an inclined wedging surface, another of said members having a projecting part` adapted to engage said wedging surface to cause said members to exert a frictional grip upon each other, one of said strap members terminating in a straight dat part; which is free to move within said seal member except for frictional contact therewith and with the other strap member.

4. A strap joint comprising overlapping strap ends, one of which has a part provided with a longitudinal inclined wedging surface, and a tubular seal embracing said strap ends and having an inwardly projecting part adapted to coact with said inclined wedging surface, the other strap end being straight and free to move within said seal except for frictional contact therewith and with the other strap end.

5. A strap joint comprising overlapping strap ends, one of which is provided with a longitudinal rib forming an inclined wedging surface diverging from the plane of the strap toward the end ther-eof, and a tubular seal embracing said overlapping strap ends and having an inwardly punched projection adapted to engage one of said strap ends and to coact with said wedging surface, the other strap end being straight and free to move within said seal except for frictional contact therewith and with the other strap end.

6. A strap joint comprising overlapping strap ends, one of which has a part provided with a longitudinally inclined wedging surface diverging away from the plane of the strap, the other strap end being straight and having opposite nat parallel surfaces throughout, and a tubular seal embracing said strap ends and having a pair of inwardly punched projections similarly located with respect to opposite ends of the seal.

- JOHN EKERN OTT. 

